Method of laminating metal to wood



2, 1966 D. KEND ETAL 9 METHOD OF LAMINATING METAL TO WOOD Filed Jan. 18,1963 25 INVENTORS if DAVID KEND BY ANTHONY CHlf-ISA United States Patent3,264,159 METHOD OF LAMINATING METAL TO WOOD David Kend, Kings Point,and Anthony Chiesa, Flushing, N.Y., assignors to Park ElectrochemicalCorporation, Flushing, N.Y., a corporation of New York Filed Jan. 18,1963, Ser. No. 252,489 2 Claims. (ill. 156-498) This invention relatesto an improved method of laminating metallic design elements to wood andthe like, and also relates to the improved resulting article.

Heretofore, in the decoration of wood surfaces with ornamental metaldesign elements, it has been necessary to cast or otherwise fabricatesuch metal design elements out of metal and secure them by cement or thelike to the wood surfaces. The ornamental effects which have beenpractical on a production basis have been relatively limited andrelatively crude in appearance.

One object of this invention is to provide an improved method ofapplying metal design elements to, wood, which will permit a variety ofornamental treatments, will permit the use of metal foil and other thinmetal stock in producing the ornamental effects and will be relativelyeasy to use on a production basis.

Another object of the invention is to provide an improved method ofapplying such design elements to wood and the like, which will at thesame time result in applying protective means to the wood surface beingtreated.

Another object of the invention is to provide the improved laminatedarticle resulting from the improved method.

In accordance with preferred embodiments of the invention, an etchingresist design corresponding to the pattern of the finished design isapplied to the front of a thin metal sheet which may be metal foil suchas aluminum foil. After the etching resist design has been cured, athin, preferably transparent, thermoplastic film or coating is appliedover the entire back of the metal foil or other thin metal sheet. Themetal sheet is then etched so as to leave only the desired metal designelement on the thermoplastic film.

The thermoplastic film with the metal design element uppermost is thenapplied to the top of a wood base which may be sheet plywood, a block orother suitable wood form. The elements are then placed in a press underheat and pressure so as to adhere the film to the wood and so as toforce the design element and film under it into the wood withcorresponding compression of the wood under the design element. Byproper design of the press platens, it is possible to produce anembossed effect. Alternatively, a fiat design face may be produced.

The use of the thermoplastic film insures good adhesion of the metaldesign elements to the wood. Furthermore, the thermoplastic film coversthe areas of the wood not covered by the design elements, therebyprotecting the wood.

Other objects and advantages of the invention will become apparent fromthe following description, in conjunction with the annexed drawing, inwhich preferred embodiments of the invention are disclosed.

In the drawing,

FIG. 1 is a top plan view of a sheet of metal foil to be treated inaccordance with the invention, such sheet being arbitrarily shown asrectangular.

FIG. 2 is a section on line 22 of FIG. 1.

FIG. 3 is a view similar to FIG. 1, showing an acid resist patternapplied to the upper surface of the metal foil. Illustratively, the wordDOE is reproduced.

FIG. 4 is a section on line 44 of FIG. 3.

FIG. 5 is a view similar to FIG. 4, showing a layer of thermoplasticfilm applied to the lower face of the metal foil after curing of theacid resist.

Patented August 2, 1966 FIG. 6 is a plan view of the article shown inFIG. 5, after the etching of all of the metal except that covered by theacid resist.

FIG. 7 is a section on line 7-7 of FIG. 6.

FIG. 8 is a view similar to FIG. 6, after the acid resist has beenremoved.

FIG. 9 is a section on line 9--9 of FIG. 8.

FIG. 10 is a sectional view similar to FIG. 9 but showing the article ofFIG. 9 applied to the top of a wooden element and adhered thereto bymeans of a press.

FIG. 11 is a view similar ot FIG. 10, but showing a second embodiment ofthe invention in which the press is modified so as to produce anembossed design.

Upon reference to the drawings in detail, it will be noted that FIG. 1shows a sheet 10 of thin metal, which may be metal foil. Such metalfoil, by way of example, but without limitation thereto, may be anodizedaluminum foil. Illustratively, sheet 10 is shown as rectangular. Thethickness of sheet 10 is optionally approximately 0.002 inch to 0.020inch.

As shown in FIG. 3, a conventional acid resist composition, which mayhave an asphalt base, is applied to the upper surface of sheet 10, suchacid resist composition being designated by the reference numeral 11.Such acid resist composition may take any suitable design form.Illustratively, such design form is shown as consisting of the lettersD, O and E to form the word DOE. It will be understood that while thedrawing shows only a single set of design elements being applied to woodat a time, it will be understood that the same process may be used toform large laminates with repeats of the design element set, which canthen be cut to individual size.

The acid resist composition 11 is cured by heat or the like, in a wellknown manner. After the curing has been completed, thermoplasticmaterial is applied evenly to the undersurface of sheet 10, so as tocover the entire surface in the form of a film 12. This film 12 may bein the "form of a thermoplastic film which is laminated to sheet 10 bymeans of heat and pressure, for example, 1000 pounds per square inch at500 degrees F. for a period of 20 minutes, which includes the time tobring the press jaws from room temperature to the 500 degrees F.temperature, and then to re-cool the jaws to room temperature. Thematerial 12 may be polyethylene or other suitable material. Preferably,the layer 12 is transparent.

As the next step in the process, an appropriate etching solution,depending upon the metal to be treated and upon the acid resistcomposition which is employed, is used so as to etch away all of themetal of sheet 10 except that covered by the acid resist composition 11.The thermoplastic material is inert to the conventional compositionsused in the etching of metals.

As will be apparent from the foregoing, the present process isparticularly easy to employ in that it utilizes standard etchingprocedures.

As shown in FIGS. 8 and 9, after the: etching, the acid resistcomposition 11 is removed by any suitable conventional means, leavingthe design elements 10a from the original sheet 10 upon thethermoplastic layer 12, these design elements 10a having the shape ofthe letters D, O and E corresponding to the original pattern of thecomposition 11.

As shown in FIG. 10, the intermediate article of FIG. 9 is applied to awood base 13, by means of the jaws 14 and 15 of a press. Such press isconventional and is not shown in detail. In this embodiment, the jaws 14and 15 have facing parallel smooth surfaces 14a and 15a. The article ofFIG. 9 is placed between the jaws with the Wood element 13 resting uponlower jaw surface 15a and with film 12 resting upon element 13 and withelements a uppermost and proximate to the upper jaw surface 14a.

The wood element 13 may be in the form of a board, a block, or plywood.Artificial or reconstituted wood products may also be employed. While inmany applications the element 13 will be relatively thin, such as 0.005inch to 0.025 inch, the invention is not so limited. If a conventionalpress is used, the wood should be thin and should have parallel planarupper and lower surfaces.

In order to produce the final product, the jaws are moved toward eachother in the direction of the respective arrows 14b and 15b, as shown inFIG. 10. The jaws are moved together under selected pressure andtemperature, in order to laminate the thermoplastic film 12 to the woodbase 13 in an appropriate manner. Since presses of this sort areconventional, the press is not shown in detail. Illustratively, thepressure may be 1000 pounds per square inch and the temperature 500degrees F. for a period of minutes which includes the time to bring thepress jaws from room temperature to the 500 degrees F. temperature andthen to re-cool the jaws to room temperature.

In this embodiment, preferably, the jaws 14 and 15 are pressed togetherso as to force the design elements 10a into the surface of the element13 so as to be flush with the upper surface thereof. As the result ofthe use of the selected heat, combined with the selected pressure, overthe selected time interval, the thermoplastic sheet material 12 becomespartially melted or tacky and is in intimate contact with the fibers ofelement 13. Upon cooling, the film 12 is permanently adhered to the wood13. Since each of the elements 10a and the film 12 thereunder is pressedinto the wood to make the upper surface of element 10a flush with themain portion of the film 12, the wood 13 is compressed in the zones 13aunder the design elements 10a. Corresponding film portions 120 arelocated under the elements 10a, recessed into the wood 13. The film 12extends from the areas 12a around the side edges of the elements 10a andhence over the main wood surface to be flush with the upper surfaces ofthe elements 10a. A

. result is to insure permanent securing of the elements 10a to the film12 and hence to the wood 13. In addition, the elements 10a arefrictionally embedded within the wood 13.

In a modification, shown in FIG. 11, the intermediate product of FIG. 9is applied to wood element 23 by means of the press jaws 24 and 25,moving in the directions of arrows 24b and 25b respectively. The woodelement 23 may correspond to the wood element 13, although in thisembodiment the wood element is preferably relatively thin to permitproper embossing of its upper surface and debossing of its lowersurface.

Press jaw 25 has male embossing dies 250 on its upper surface 25acorresponding in shape, orientation, and size to the design elements10a. law 24 has female die elements 240 in its lower surface 24a of thesame shape and orientation as elements 10a. The female elements 24c areof greater size than the male elements 25c.

It will be understood that the article of FIG. 9 is placed in the presswith the die elements 240 and 250 and the design elements 10a inregistration. When the parallel jaw faces 24a and 25a are pressedtogether, for appropriate time interval and appropriate pressure andtemperature, the lower surface of wood element 23 is debossed at 23acorresponding to the die element 250. The wood element portion 23b andcorresponding portions of film 12, as well as the design element 10a,are embossed into the female die element 240. At the same time, the flatupper surface of the die element 24c causes the element 10a and theplastic film 12a under it to be embedded into the surface of theembossed wood element portion 23b, in the same manner as in the firstembodiment. Accordingly, it is possible to produce an embossed design,in which the element 10a is still surrounded on its side edges by theplastic film and together with the plastic film is embedded into thesurface of the wood to add mechanical frictional strength to hold thedesign element in place. At the same time, in view of the transparencyof the film 12, a true visual effect of the embossmcnt of the element10a only is produced corresponding to the embossed effect which would beachieved if a conventional thick metal design element were used.

The invention is not limited to the wood base. Thus, a thermoplastic,normally relatively rigid base may be substituted for-the wood base, andthe sheet 12 carrying the foil design elements may be laminated to suchplastic base under heat and pressure or by any other suitable means.Such base need not be thermoplastic in the event that cement or othersuitable adhering means is employed.

While preferred embodiments of the invention have been disclosed, andvarious possible changes, omissions and additions have been indicatedtherein, it will be apparent that various other changes, omissions andadditions may be made in the invention without departing from the scopeand spirit thereof.

What is claimed is:

1. Method of applying a plurality of discrete metal design elements to abase of wood and the like, comprising:

(a) adhering a thin thermoplastic film over the entire back of a metalfoil sheet having a thickness of approximately 0.002 inch to 0.020 inch;

(b) removing portions of the metal foil sheet so as to leave only thediscrete metal design elements on the thermoplastic film; and

(c) applying the thermoplastic film with metal design elements uppermostto the top of the base and pressing the assembly under heat and pressureto adhere the film to the base and to force the design elements and filmunder them into the base with corresponding compression of the baseunder the design element.

2. Method according to claim 1, said design elements and film beingforced into the work to make said design elements substantially flushwith the film extending over the entire top of said wood base.

References Cited by the Examiner UNITED STATES PATENTS ALEXANDER WYMAN,Primary Examiner.

JACOB STEINBERG, Examiner.

W. POWELL, Assistant Examiner.

1. METHOD OF APPLYING A PLURALITY OF DISCRETE METAL DESIGN ELEMENTS TO ABASE OF WOOD AND THE LIKE, COMPRISING: (A) ADHERING A THIN THERMOPLASTICFILM OVER THE ENTIRE BACK OF A METAL FOIL SHEET HAVING A THICKNESS OFAPPROXIMATELY 0.002 INCH TO 0.020 INCH; (B) REMOVING PORTIONS OF THEMETAL FOIL SHEET SO AS TO LEAVE ONLY HE DISCRETE METAL DESIGN ELEMENTSON THE THERMOPLASTIC FILM; AND (C) APPLYING THE THERMOPLASTIC FILM WITHMETAL DESIGN ELEMENTS UPPERMOST TO THE TOP OF THE BASE AND PRESSING THEASSEMBLY UNDER HEAT AND PRESSURE TO ADHERE THE FILM TO THE BASE AND TOFORCE THE DESIGN ELEMENTS AND FILM UNDER THEM INTO THE BASE WITHCORRESPONDING COMPRESSION OF THE BASE UNDER THE DESIGN ELEMENT.